Persistence of vision, subliminal spot light

ABSTRACT

A spot light with a reflector, wherein both the reflector and the light filament, or just a reflector surrounding a stationary bulb rotate at speeds in excess of 600 revolutions per minute, thereby simultaneously concentrating and intensifying a beam of light and likewise dispersing the the beam horizontally a full 360*. By the phenonmenon of the approximate one-tenth of a second persistence of vision of the human eye, the entire circular area traversed by the rotating beam, when the motor exceeds 600 revolutions per minute, has the same apparent intensity of light and the same luminosity that any segment of the same circle would have that was lighted only by the arc cast by the same spot light in a stationary position. The threshold of discrimination of the human eye and the approximate one-tenth of a second after-image on the retina create an apparent, steady, intensified beam of light in an arc of 360*.

111 3,865,790 1 Feb. 11, 1975 PERSISTENCE OF VISION, SUBLIMINAL SPOT LIGHT Primary Examiner-Richard M. Sheer [57] ABSTRACT A spot light with a reflector,,whe:rein both the reflector and the light filament, or just a reflector surrounding a stationary bulb rotate at speeds in excess of 600 revolutions per minute, thereby simultaneously concentrating and intensifying a beam of light and likewise dispersing the the beam horizontally a full 360. By the phenonmenon of the approximate one-tenth of a second persistence of vision of the human eye, the entire circular area traversed by the rotating beam, when the motor exceeds 600 revolutions per minute, has the same apparent intensity of light and the same luminosity that any segment of the same circle would have that was lighted only by the arc cast by the same spot light in a stationary position. The threshold of discrimination of the human eye and the approximate one-tenth ofa second after-image on the retina create an apparent, steady, intensified beam of light in an arc of 360.

5 Claims, 5 Drawing Figures PATENIEU E 3.865.790

sum 2 0F 4 FIG. 3

sum 30F 4 PATENIEUFEBI 1 ms FIG.5

vvhvrw PERSISTENCE OF VISION, SUBLIMINAL SPOT LIGHT SUMMARY OF THE INVENTION This invention relates primarily to a rapidly rotating spot light, and included in the objects of the invention are:

First, to provide a spot light design that concentrates I a beam of light by means of a reflector and then rotates the beam of light at speeds exceeding 600 revolutions per minute to diffuse and horizontally spread the concentrated beam of light in a 360 arc.

Second, to provide a spot light design that permits a reflector and bulb or a sealed beam type of lamp to be rotated at speeds in excess of 600 revolutions per minute without rupturing the filament.

Third, to provide an accessory double reflector formed by two semi-circular planes of material intersecting at approximately 90. When the semi-circular double reflector is attached to the casing, it vertically doubles the beam of light and concentrates that broadened beam on a selected 180 of terrain. By means of a double reflection, the reflector reverses an arc oflight of approximately 180.

Fourth, to provide a second accessory reflector formed by a flat plane curved into a semi-circle, which when used in conjunction with the semi-circular, double reflector, allows the light source to be placed in a recess out of the line of sight to guard the light source against damage by propelled objects and still to project a vertically broadened beam over an approximate 180 arc of the surrounding terrain.

With the above and other objects in view, as may appear hereinafter, reference is directed to the accompanying drawings in which:

FIG. 1 is a diagrammatical, cross-sectional side view of the light assembly, indicating the motor, the battery storage area, the rotating light source and the wiring.

FIG. 2 is a fragmentary cross sectional top view, essentially diagrammatical, of the lamp assembly to show the position of the essential parts.

FIG. 3 is a diagrammatical, cross-sectional view, showing the path of light, when the semi-circular, double reflector is attached to the light assembly.

FIG. 4 is a top view in blue print form of the semicircular, double reflector.

FIG. 5 is a diagrammatical view illustrating the application of the semi-circular, double reflector and the flat, curved reflector, also the path of light traversed, when the light source is placed in a recess for protection.

This invention relates to a spot light that can rotate a beam of light in excess of 600 revolutions per minute without the light source or the filament rupturing. When the lamp and reflector are rotated at speeds in excess of 600 revolutions per minute, the phenomenon of the persistence of vision of the human eye (as with motion pitures and the after-image on the retina) causes the eye to perceive a circular area lighted with the same apparent luminosity and steady intensity as any segment or arc of the same circle of light that would be illuminated by the same spot light, if the spot light were not in motion.

With reference to FIG. 1, a motor 21 that is capable of more than 600 revolutions per minute is mounted on a baseplate 23. The filament 6 and the motor 21 are supplied current by a car battery 29 or other power source. Both the lamp filament 6 and the motor 21 are activated by an on-off switch 28. The revolutions per minutes of the motor 21 are controlled by a rheostat 27.

The area 25 inside the casing surrounding the motor 21 is a storage space to be used as a battery container 25 to convert the persistence of vision subliminal spot light into an independent, self-contained unit.

To allow the spot light to rotate freely, the electrical power is conducted to the lamp filament 6, as shown in FIG. 1, by means of the brushes 17, 18 sliding over the conducting rings 15, 16, which in turn transfer the current to the wires 15a, 16a leading to the filament 6 on the rotating assembly. The wires 15a, 16a are connected to the rings 15, 16 on the motor shaft 14. The conducting rings 15, 16 are insulated from the motor shaft 14.

The lamp can be either of two types: an automotive sealed beam or a lamp with a replaceable bulb (not illustrated).

With reference to FIGS. 1 and. 2, the lamp filament 6 should be positioned vertically as closely as possible to the spin axis of the motor shaft 14 in order to reduce the centrifugal force on the Lamp filament 6 to an absolute minimum to prevent breakage or rupture of the lamp filament 6. The lamp filament 6 is centered by sliding the Lamp socket bracket 8 and the lamp support bracket 3 along the adjustment slots l2, 13 in the rotating support bar 9. When the filament 6 coincides with the spin axis of the motor shafts 14, the brackets 8, 9 are tightened securely.

The lamp lens 4 should be clear to avoid horizontal dispersion of the light beam. A parabolic reflector, as illustrated, is preferable in order to concentrate the beam of light into a strong, narrow, vertical beam, because the rotation will give all the horizontal dispersion of light that is necessary. The hood 1 is made of transparent material.

With reference to FIGS. 1 and 2, the two balance weights 10, 10a balance the weight of the rotating assembly about the spin axis of the: motor shaft 14. The balance weights 10, 10a are positioned by means of the adjustment Slots 11, 11a in the rotating support bar 9.

Reference is made to FIG. 3 to illustrate the use of the Semi-circular double reflector 30. The double reflector 30 is attached to the casing 22 by inserting the tab 31 on the double reflector 30 into the reflector mount 24 on the casing 22. As illustrated in FIG. 3, the semi-circular double reflector 30 reverses the direction of an approximate arc of light to double the vertical thickness of the beam, thereby doubling and concentrating a thicker beam of light onto a scene of activ ity where it might be needed.

Reference is made to FIG. 5 to illustrate the flat, curved reflector 32, when it is used in conjunction with the semi-circular, double reflector 30. The primary purpose of the flat curved reflector 32 is to again reverse the two beams of light: the one cast by the light source and the one cast by the semhcircular double reflector 30. The Light Unit can then be placed in a recess, protecting it from possible damage by vandalism, bullets, or propelled objects. In its application in police work or in a prison, damage from bullets or propelled objects would only occurr to the flat curved reflector 32, which would show only the image of the light source above the ground.

I also recognize and lay claim to the apparent conversion and modification of the lamp assembly for use with a stationary bulb by mounting a standard light bulb socket in the top 2 of the hood 1 using means well known in the art and inserting a bulb mounted in the socket through a hole in the parabolic reflector 5.

While particular embodiments of this invention have been shown and described, it is not intended to limit the same to the details of the construction set forth, but instead the invention embraces such changes, modifications and equivalents of the various parts and their relationships as come within the purview of the appended claims:

I claim:

1. A self-contained spot light assembly comprising:

a. a housing having a transparent top section;

b. an electric lamp having a filament mounted within the transparent top section of said housing;

c. reflector means rotatably mounted about an axis centered through the filament in said lamp within the transparent top section of said housing for concentrating a beam of light emitted by said lamp into a strong narrow beam and projecting the beam through the transparent top section of said housing;

d. means mounted within said housing and secured to said reflector means for continuously rotating said reflector means at speeds of at least about 600 rpm to project a concentrated beam of light a full 360 through the transparent top section of said housing;

e. means within the transparent top section for adjusting said reflector means with respect to said rotating means for rotation about the axis centered through said lamp filament;

f. means within the transparent top section for adjusting the balance of said rotatably mounted reflector means with respect to said rotating means about the axis of rotation;

g. electric power source means within said housing for said lamp and said reflector rotating means; and

h. means mounted in said housing for varying the speed of rotation of said reflector rotating means.

2. The spot light assembly of claim I wherein said means for rotating said reflector means comprises means for concurrently rotating said lamp and reflector means.

3. The spot light assembly of claim 1 wherein said electric power means comprises batteries stored in said housing.

4. The spot light assembly of claim 1 comprising reflector means mounted on said housing outside the transparent top section thereof to intercept a portion of the concentrated beam of light projecting through the transparent top section of said housing and project in a reverse direction a concentrated beam of light of increased vertical direction.

5. The spot light assembly of claim 4 wherein the reflector means mounted on said housing comprises a reflector composed of two intersecting planar surfaces arranged to intercept light projecting through about 180 of said transparent top section and project in the reverse direction of about l a concentrated beam of light of increased vertical dimension. 

1. A self-contained spot light assembly comprising: a. a housing having a transparent top section; b. an electric lamp having a filament mounted within the transparent top section of said housing; c. reflector means rotatably mounted about an axis centered through the filament in said lamp within the transparent top section of said housing for concentrating a beam of light emitted by said lamp into a strong narrow beam and projecting the beam through the transparent top section of said housing; d. means mounted within said housing and secured to said reflector means for continuously rotating said reflector means at speeds of at least about 600 rpm to project a concentrated beam of light a full 360* through the transparent top section of said housing; e. means within the transparent top section for adjusting said reflector means with respect to said rotating means for rotation about the axis centered through said lamp filament; f. means within the transparent top section for adjusting the balance of said rotatably mounted reflector means with respect to said rotating means about the axis of rotation; g. electric power source means within said housing for said lamp and said reflector rotating means; and h. means mounted in said housing for varying the speed of rotation of said reflector rotating means.
 2. The spot light assembly of claim 1 wherein said means for rotating said reflector means comprises means for concurrently rotating said lamp and reflector means.
 3. The spot light assembly of claim 1 wherein said electric power means comprises batteries stored in said housing.
 4. The spot light assembly of claim 1 comprising reflector means mounted on said housing outside the transparent top section thereof to intercept a portion of the concentrated beam of light projecting through the transparent top section of said housing and project in a reverse direction a concentrated beam of light of increased vertical direction.
 5. The spot light assembly of claim 4 wherein the reflector means mounted on said housing comprises a reflector composed of two intersecting planar surfaces arranged to intercept light projecting through about 180* of said transparent top section and project in the reverse direction of about 180* a concentrated beam of light of increased vertical dimension. 